CN105567290B - A kind of method for reducing ethylene unit energy consumption - Google Patents
A kind of method for reducing ethylene unit energy consumption Download PDFInfo
- Publication number
- CN105567290B CN105567290B CN201410542715.XA CN201410542715A CN105567290B CN 105567290 B CN105567290 B CN 105567290B CN 201410542715 A CN201410542715 A CN 201410542715A CN 105567290 B CN105567290 B CN 105567290B
- Authority
- CN
- China
- Prior art keywords
- oil
- tower
- solvent
- ethylene unit
- energy consumption
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
- Active
Links
Abstract
The invention discloses a kind of method for reducing ethylene unit energy consumption, it is characterised in that the cracking gas of cracking outlet of still sends into oil scrubber after being cooled down through quencher, carries out material separation, and quench oil is drawn from oil scrubber bottom of towe, and part quench oil is sent to quencher；Part quench oil returns to oil scrubber；Part quench oil enters extraction tower carries out solvent extraction, and extraction tower materials at bottom of tower pitch is mutually drawn, and extraction tower tower top material isolates solvent and visbreaking quench oil through being depressured laggard solvent recovery tower, and visbreaking quench oil returns to oil scrubber, and solvent returns to extraction tower.
Description
Technical field
It is to be related to a kind of method for reducing ethylene unit energy consumption furtherly the present invention relates to ethylene production field.
Background technology
At present, main ethylene unit produces ethene, propylene, butadiene, aromatic hydrocarbons etc. using steam thermal cracking process in the world
Basic organic chemical raw material.The raw materials such as lighter hydrocarbons, naphtha, hydrogenation tail oil are blended in industrial crack with a certain proportion of dilution steam generation
There is cracking reaction in stove under hot conditions, pyrolysis product through the operation final production such as over-quenching, compression, separation go out ethene,
The industrial chemicals such as propylene, butadiene.
Chilling system is the throat of ethylene unit, and it is made up of equipment such as quencher, oil scrubber, water scrubbers, is carry point
From cracking distillate (gasoline, diesel oil, fuel oil) component and the task of recovery process water, while still reclaiming heat in cracking process
The key equipment of amount.The cracking gas that the outlet of industrial pyrolysis furnace waste heat boiler comes sends into oil in quencher after quench oil spraying cooling
Tower bottom is washed, after backflow cooling, the light component in pyrolysis product continues cool to 40 from oil scrubber Base top contact into water scrubber
DEG C or so, into follow-up compression piece-rate system.
, all from the UTILIZATION OF VESIDUAL HEAT IN of device inside quench oil, minority is or not most of dilution steam generation required for cracking process
Foot point is supplemented by pipe network steam.Oil scrubber bottom temperature is higher, more, device by utilizing waste heat better, the outer benefit of utilization of steam generation
Steam consumption is fewer.Therefore the height of oil scrubber bottom temperature directly determines the size of waste heat recovery volume, the fortune of chilling system
The bad energy consumption height to ethylene unit of acting charitably has important influence, so as to also contribute to the production cost of device.
Regard ethylene unit chilling system as an entirety, inflow is pyrolysis product, and outflow is cracking gas and cracking
Distillate；Quench oil, process water etc. are in system interior circulation.Therefore ethylene unit chilling system runs well will ensure two
Balance, heat balance, material balance.Heat balance is that the heat for bringing chilling system into by cracking gas will be by occurring dilution steam generation
Utilize Deng heat exchange mode.Material balance is then relative complex, because pyrolysis product can occur polymerization etc. instead after entering chilling system
Answer, produce change, chilling system is needed the pyrolysis product discharge after change, stable with component in keeping chilling system.
Ethylene quenching system practical problem now aborning is exactly low oil scrubber bottom temperature, and chilling oil viscosity is high.It is anxious
Cold oil bottom temperature is low, and dilution steam generation temperature difference of heat exchanger is small, dilution steam generation generating capacity wretched insufficiency, it is therefore desirable to which a large amount of steam are mended
Enter system；Chilling oil viscosity is high, and the power consumption of quenching oil circulation pump is high, causes ethylene unit energy consumption to remain high, when viscosity is too high
Can also blocking pipeline cause parking.
The reason for causing ethylene quenching system problem is exactly that the asphalitine of generation in quench oil cannot be discharged in time.In order to give
The cracking gas cooling that pyrolysis furnace is produced, quench oil is circulated between quencher and oil wash tower reactor in chilling system, and its internal circulating load is past
It is past to reach thousands of tphs, and the extraction for cracking distillate only has tens tphs, quench oil is stagnant for a long time in system
Stay, produce a large amount of asphalitines, viscosity significantly to raise.And in order to control chilling oil viscosity, oil wash bottom temperature can only be reduced to subtract
The speed of few asphalitine generation.But oil wash bottom temperature is reduced in the case of pyrolysis furnace load identical, quench oil can be increased
Internal circulating load, so that the time that quench oil is detained in system is longer, increased the amount of asphalitine generation again.So actual production
In oil wash bottom temperature can only be maintained 180 DEG C or so, just can guarantee that the pitch of the asphalitine and discharge generated in quench oil
Matter balances each other, and maintains quench oil viscosity stabilization.Here it is 210 DEG C of oil scrubber tower reactor design temperature, can actual motion less than 190 DEG C
Basic reason.
At present, using adding quenched flux oil, adding viscosity reductant and using three kinds of methods of visbreaking tower on commercial plant, can only
It is cost to reduce oil scrubber bottom temperature, chilling oil viscosity is controlled reluctantly, causes ethylene unit energy consumption to remain high.
First method is to add quenched flux oil (pyrolysis gas oil) reduction viscosity, largely pyrolysis gas oil will be blended to urgency
In cold oil, its side effect is very big.First, internal circulating load of the pyrolysis gas oil in oil scrubber can be increased, oil scrubber tower reactor to tower is increased
The gas phase load at middle part, correspondingly reduces the disposal ability of oil scrubber；Secondly, in pyrolysis gas oil containing substantial amounts of styrene,
The components such as naphthalene, indenes, when they are circulated with quench oil, it may occur that polymerisation produces polymer, and accumulates in oil scrubber
On column plate or filler, heat transfer and the mass transfer effect of influence column plate and filler rise tower pressure difference, and the disposal ability of tower declines；Again
It is secondary, due to the increase of pyrolysis gas oil internal circulating load, part can be contained in the Pyrolysis fuel oil PFO of drippolene and the tower reactor extraction of tower top
The component of diesel oil, has influence on the quality of drippolene and fuel oil, can cause that the operation of follow-up quenching water column deteriorates when serious；
Finally, due to the amount of quench oil is very big, therefore in order to reduce the viscosity of quench oil, it usually needs substantial amounts of cracking bavin is mixed for a long time
Oil.In this way, it is impossible to reduce asphalitine growing amount, chilling oil viscosity can only be typically controlled in 1000~2000mm2/s
(50 DEG C), oil scrubber bottom temperature is without significantly improving.
Viscosity reductant be in recent years domestic and international research department and ethene patent business work out it is various it is suitable reduction quench oils glue
The chemical agent of degree, visbreaking target is realized by adding the activity of chemical assistant suppression polymerisation free radical.CN
101062880A proposes a kind of Reduce viscosity agent being made up of polymerization inhibitor, dispersant and matal deactivator, be polymerized with suppression,
Prevent aggregation and the effect of passivating metallic surfaces.Although add viscosity reductant reduces the formation speed of asphalitine to a certain extent,
It is do not have any help to asphalitine discharge chilling system, it is impossible to fundamentally solve that chilling oil viscosity is high and oil scrubber tower reactor temperature
The low problem of degree.Actually used middle viscosity reductant is seldom used alone, and is while using visbreaking tower technology, to be made with viscosity reductant
It is supplementary means.
Visbreaking tower technology is the quench oil that will be exported from quenching oil circulation pump, under the control of temperature control valve (TCV), with
The ethane cracking gas that Control for Pyrolysis Furnace Area is come is contacted in nozzle mixer, and the light component in quench oil is vaporized, with cracking gas
Into visbreaking tower.The light component vaporized in ethane cracking gas and quench oil enters oil scrubber tower reactor, non-vapour from visbreaking column overhead
The heavy liquid phase component of change enters visbreaking tower tower reactor, used as byproduct (Pyrolysis fuel oil PFO) output to tank field.So, it is selective
Ground fractionates out the heavier feeds containing more asphalitine from quench oil and stays in systems light material, makes circulation quench oil
In light components concentration increase, so as to reduce quench oil viscosity.But in fact, visbreaking column overhead temperatures are at 250-290 DEG C, only
Light component below this temperature can be returned to oil scrubber, there are a large amount of low viscous components in the fuel oil of discharge, discharge pitch
Efficiency it is low.Simultaneously as quench oil will be contacted with 500 DEG C or so of ethane stove cracking gas, stop increased urgency at high temperature
Cold oil studies on asphaltene growing amount, adversely affects to chilling oil viscosity.In actual motion, can only be by oil scrubber bottom temperature
180 DEG C or so are limited in, chilling oil viscosity can be just controlled.
Especially, cracking stock progressively lighting in recent years, because the Pyrolysis fuel oil PFO for producing is little, under identical internal circulating load
Discharge rate is smaller, and quench oil holdup time in system is longer, and the asphalitine of generation is more, and what can be discharged is less so that existing
Technology loses effect substantially.Prior art can only be reduced due to the asphalitine discharge that will effectively cannot be generated in quench oil
The temperature of oil scrubber tower reactor controls chilling oil viscosity, considerably increases ethylene unit energy consumption.Therefore, it is badly in need of a kind of skill of exploitation
Art, while chilling oil viscosity is controlled, improves quenching oil column bottom temperature, reduces ethylene unit comprehensive energy consumption.
The content of the invention
To solve problems of the prior art, the invention provides a kind of method for reducing ethylene unit energy consumption.It is logical
Cross solvent extraction and step-down is reclaimed, reduce the viscosity of quench oil, by improving oil scrubber bottom temperature to improve chilling oil temperature,
And then increasing dilution steam generation yield, the solvent after separation is recycled, and reduces the comprehensive energy consumption of ethylene unit.
It is an object of the invention to provide a kind of method of above-mentioned reduction ethylene unit energy consumption, it is characterised in that cracking
The cracking gas that outlet of still comes sends into oil scrubber after being cooled down through quencher, carries out material separation, and quench oil is drawn from oil scrubber bottom of towe,
Part quench oil is sent to quencher；Part quench oil returns to oil scrubber；Part quench oil enters extraction tower carries out solvent extraction, extracting
Tower materials at bottom of tower pitch is mutually drawn, and extraction tower tower top material isolates solvent and visbreaking chilling through being depressured laggard solvent recovery tower
Oil, visbreaking quench oil returns to oil scrubber, and solvent returns to extraction tower.
Oil scrubber bottom temperature of the invention brings up to 190-250 DEG C, is preferably increased to 195-235 DEG C.
During extraction tower solvent extraction, solvent is 0.01-20, preferably 0.5-5 with the weight ratio of quench oil；Extracting pressure tower
It is 0.5MPa-10MPa, the temperature of extraction tower is 0 DEG C -250 DEG C.
Described solvent is selected from the one kind or its mixture in C2-C6 alkane or alkene, preferably in C3-C5 alkane
Plant or its mixture.
Described quench oil is the oil distillate of oil scrubber tower reactor in ethylene unit chilling system, and its typical composition is many cyclophanes
Hydrocarbon, colloid, asphalitine.Described ethylene unit is mainly made up of the system such as industrial pyrolysis furnace and chilling, compression, separation, chilling
System mainly includes quencher, oil scrubber, water scrubber.
The recovery pressure tower used during solvent recovery is 0.1MPa-5Mpa, and temperature is 0 DEG C -250 DEG C.
The method of the present invention can specifically use following technical scheme：
The high-temperature split product (containing the composition such as from H2 to Pyrolysis fuel oil PFO, also comprising dilution steam generation) of outlet of still is cracked,
Enter quencher 4 after waste heat boiler reclaims heat and is cooled, with quench oil directly contact, cooling.Cracking after cooling
Gas and quench oil enter oil scrubber 1 together, carry out Oil-gas Separation, and tower reactor draws circulation quench oil, into Dilution steam generator
8, produce dilution steam generation.
It is divided into three tunnels after circulation quench oil is cooled, pyrolysis furnace quencher 4 is removed all the way；All the way by technique water preheater 9
Oil scrubber is returned again to, after leading up to the pressurization of booster pump 5, into the quench oil charging aperture of extraction tower 2.
Solvent enters the solvent feed mouthful of extraction tower 2, and solvent implements extracting with quench oil in extraction tower 2, and what is obtained takes out
The extracting oil export of oily (mixture of solvent and quench oil light component) from the top of extraction tower is carried to draw, the raffinate pitch for obtaining from
The asphalt outlet for extracting tower bottom is drawn.
Extract oil by pressure-reducing valve 10 reduction pressure after, through 7 liters of high-temperatures of heat exchanger, into the import of solvent recovery tower 3.Take out
Carry oil and circulation solvent and visbreaking quench oil are separated into solvent recovery tower, circulation solvent is drawn from column overhead is reclaimed, visbreaking urgency
Cold oil is drawn from bottom of towe.
After the circulation solvent drawn by solvent recovery tower 3 increases pressure through compressor 11, extract oil is added into heat exchanger 7
Heat, while oneself is lowered the temperature, then lowers the temperature through subcooler 6.After cycle of higher pressure solvent after cooling mixes with supplementing solvent, make again
For the solvent of extraction tower enters the solvent feed of extraction tower 2 mouthful.
The visbreaking quench oil drawn from solvent recovery tower returns to oil scrubber 1, so as to effectively reduce overall chilling oil viscosity.Carry
The bottom temperature of ethylene unit chilling system oil scrubber 1 high, improves the generating capacity of dilution steam generation, reduces ethylene unit energy consumption.
The present invention by solvent extraction and step-down desolventizing reduction chilling oil viscosity, and by heat exchanger by chilling oil solvent
Hot and cold stream stock in extraction system carries out energy exchange, heating and cooling energy is reduced, by improving oil scrubber bottom temperature
Increase dilution steam generation steam exhaling amount, improve ethylene unit heat recovery efficiency, reduce the energy consumption of ethylene unit.
Brief description of the drawings
Fig. 1 system schematics of the invention
Description of reference numerals：
1 oil scrubber, 2 extraction towers, 3 solvent recovery towers, 4 quenchers, 5 booster pumps, 6 coolers, 7 heat exchangers, 8 dilution steam generations
Generator, 9 preheaters, 10 pressure-reducing valves, 11 compressors
Specific embodiment
With reference to embodiment, the present invention is further illustrated.
Embodiment
Certain ethylene unit produces 200kt/a, year operation 8000h, ethylene yield 25t/h per year.Crack the Pintsch process of outlet of still
Gas (contains from H2Constituted to Pyrolysis fuel oil PFO etc., also comprising dilution steam generation), after waste heat boiler reclaims heat and is cooled,
Total amount is 147t/h, into quencher, with quench oil directly contact, cooling.Cracking gas and quench oil after cooling enter together
Oil scrubber, carries out Oil-gas Separation, and tower reactor draws circulation quench oil, into Dilution steam generator, produces dilution steam generation, and circulation is anxious
Cold oil total amount is 1200t/h.It is divided into three tunnels after quench oil is cooled, pyrolysis furnace quencher is removed all the way；It is pre- by process water all the way
Hot device returns again to oil scrubber, and enter carries out solvent extraction all the way in extraction tower, from restructuring of the extracting tower bottom removing based on pitch
Divide 1.5t/h.After the oil phase step-down that extracting tower top is obtained, by heat exchanger, subsequently into solvent recovery tower, visbreaking urgency is separated into
Cold oil and circulation solvent.Visbreaking quench oil returns to oil scrubber, reduces chilling oil viscosity.Circulation solvent passes through heat exchanger and cooler
Recycled into extraction tower after reducing temperature.Specific embodiment process conditions are as follows.
Comparative example 1
Certain ethylene unit produces 200kt, year operation 8000h, ethylene yield 25t/h per year, and chilling system charging total amount is 147t/
H, oil scrubber bottom draw circulation quench oil by Dilution steam generator generation dilution steam generation, then go pyrolysis furnace quencher to
Oil scrubber is returned after cracking gas cooling.Chilling oil viscosity 2000mm2/ s, consumes tempering oil 4t/h, and oil scrubber bottom temperature is 178
DEG C, generation dilution steam generation only has 12t/h, ethylene unit energy consumption 643GJ/h.
Claims (8)
1. it is a kind of reduce ethylene unit energy consumption method, it is characterised in that cracking outlet of still cracking gas through quencher cool down
After send into oil scrubber, carry out material separation, draw quench oil from oil scrubber bottom of towe, part quench oil is sent to quencher；Part is anxious
Cold oil returns to oil scrubber；Part quench oil enters extraction tower carries out solvent extraction, and extraction tower materials at bottom of tower pitch is mutually drawn, extraction tower
Tower top material isolates solvent and visbreaking quench oil through being depressured laggard solvent recovery tower, and visbreaking quench oil returns to oil scrubber, solvent
Return to extraction tower；Solvent carries out heat exchange before returning to extraction tower with the extraction tower tower top material after step-down；Oil scrubber tower reactor temperature
Spend is 190-250 DEG C.
2. the method for reducing ethylene unit energy consumption as claimed in claim 1, it is characterised in that oil scrubber bottom temperature is 195-
235℃。
3. the method for reducing ethylene unit energy consumption as claimed in claim 1, it is characterised in that the solvent is selected from C2-C6
One kind of alkane or its mixture.
4. the method for reducing ethylene unit energy consumption as claimed in claim 3, it is characterised in that the solvent is selected from C3-C5
One kind or its mixture in alkane.
5. the method for reducing ethylene unit energy consumption as claimed in claim 1, it is characterised in that enter the solvent and urgency of extraction tower
The weight ratio of cold oil is 0.01-20.
6. the method for reducing ethylene unit energy consumption as claimed in claim 5, it is characterised in that enter the solvent and urgency of extraction tower
The weight ratio of cold oil is 0.5-5.
7. the as claimed in claim 1 method for reducing ethylene unit energy consumption, it is characterised in that the pressure of the extraction tower is
0.5MPa-10MPa, tower top temperature is 0 DEG C -250 DEG C.
8. the method for reducing ethylene unit energy consumption as claimed in claim 1, it is characterised in that the pressure of the solvent recovery tower
It is 0.1MPa-5MPa, temperature is 0 DEG C -250 DEG C.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201410542715.XA CN105567290B (en) | 2014-10-14 | 2014-10-14 | A kind of method for reducing ethylene unit energy consumption |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201410542715.XA CN105567290B (en) | 2014-10-14 | 2014-10-14 | A kind of method for reducing ethylene unit energy consumption |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| CN105567290A CN105567290A (en) | 2016-05-11 |
| CN105567290B true CN105567290B (en) | 2017-06-30 |
Family
ID=55877933
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CN201410542715.XA Active CN105567290B (en) | 2014-10-14 | 2014-10-14 | A kind of method for reducing ethylene unit energy consumption |
Country Status (1)
| Country | Link |
|---|---|
| CN (1) | CN105567290B (en) |
Families Citing this family (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN111088061B (en) * | 2018-10-24 | 2021-08-03 | 中国石油化工股份有限公司 | System and method for viscosity reduction |
| CN111088060B (en) * | 2018-10-24 | 2021-08-03 | 中国石油化工股份有限公司 | System and method for viscosity reduction |
Citations (4)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN103305257A (en) * | 2012-03-16 | 2013-09-18 | 中国石油化工股份有限公司 | Method for reducing viscosity of quenching oil of ethylene unit |
| CN103305260A (en) * | 2012-03-16 | 2013-09-18 | 中国石油化工股份有限公司 | System and method for reducing viscosity of quenching oil of ethylene unit |
| CN103305258A (en) * | 2012-03-16 | 2013-09-18 | 中国石油化工股份有限公司 | Method for reducing viscosity of quenching oil of ethylene unit |
| CN103305259A (en) * | 2012-03-16 | 2013-09-18 | 中国石油化工股份有限公司 | Method for reducing viscosity of quenching oil of ethylene unit |
-
2014
- 2014-10-14 CN CN201410542715.XA patent/CN105567290B/en active Active
Patent Citations (4)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN103305257A (en) * | 2012-03-16 | 2013-09-18 | 中国石油化工股份有限公司 | Method for reducing viscosity of quenching oil of ethylene unit |
| CN103305260A (en) * | 2012-03-16 | 2013-09-18 | 中国石油化工股份有限公司 | System and method for reducing viscosity of quenching oil of ethylene unit |
| CN103305258A (en) * | 2012-03-16 | 2013-09-18 | 中国石油化工股份有限公司 | Method for reducing viscosity of quenching oil of ethylene unit |
| CN103305259A (en) * | 2012-03-16 | 2013-09-18 | 中国石油化工股份有限公司 | Method for reducing viscosity of quenching oil of ethylene unit |
Also Published As
| Publication number | Publication date |
|---|---|
| CN105567290A (en) | 2016-05-11 |
Similar Documents
| Publication | Publication Date | Title |
|---|---|---|
| CN103305259B (en) | A kind of method reducing ethylene unit quenching oil viscosity | |
| CN103305257B (en) | Method for reducing viscosity of quenching oil of ethylene unit | |
| CN105154134B (en) | Method for preparing catalytic thermal cracking raw materials from full-fraction shale oil | |
| CN103305260B (en) | A kind of system and method reducing ethylene unit quenching oil viscosity | |
| CN101323553B (en) | Method for improving ethylene apparatus quench oil tower bottom temperature | |
| CN102220169B (en) | Pyrolysis gas quenching structural unit of CPP (Catalytic Pyrolysis Production) and process thereof | |
| CN105566029B (en) | A kind of method for reducing ethylene unit energy consumption | |
| CN105567290B (en) | A kind of method for reducing ethylene unit energy consumption | |
| CN103305258B (en) | Method for reducing viscosity of quenching oil of ethylene unit | |
| CN105567292B (en) | A kind of method for reducing ethylene unit energy consumption | |
| CN105567294B (en) | A kind of method for reducing ethylene unit energy consumption | |
| CN105567291B (en) | A kind of method for reducing ethylene unit energy consumption | |
| CN105505436B (en) | A kind of method for reducing ethylene unit energy consumption | |
| CN105567296B (en) | A kind of method for reducing ethylene unit energy consumption | |
| CN104449820B (en) | A kind of method that reduces the system of ethylene unit quench oil viscosity and improve solvent recovering rate | |
| CN101962565A (en) | Quench oil viscosity reducing process for two quench oil systems | |
| CN210462963U (en) | Dilute steam generator capable of controlling steam/hydrocarbon ratio for light hydrocarbon thermal cracking | |
| CN105567295B (en) | A kind of method for reducing ethylene unit energy consumption | |
| CN115716771A (en) | Quenching oil system and quenching method of ethylene cracking device | |
| CN104449807B (en) | A kind of quenching oil extracting visbreaking system | |
| CN105713647B (en) | A kind of utilization coal tar maximization prepares the method and device of carbolic oil and diesel oil | |
| CN104449827B (en) | A kind of system and method reducing ethylene unit quench oil viscosity | |
| CN105567293B (en) | A kind of method for reducing ethylene unit energy consumption | |
| CN104449826B (en) | A kind of method that reduces ethylene unit quench oil viscosity | |
| CN104449825B (en) | A kind of method reducing ethylene unit quenching oil viscosity and improve solvent recovering rate |
Legal Events
| Date | Code | Title | Description |
|---|---|---|---|
| C06 | Publication | ||
| PB01 | Publication | ||
| C10 | Entry into substantive examination | ||
| SE01 | Entry into force of request for substantive examination | ||
| GR01 | Patent grant | ||
| GR01 | Patent grant |